1. Field of the Invention
The present invention relates to a hydraulic shock absorber with a self leveling function for a vehicle height and in particular, to an improvement of a relief valve which prevents a rapid increase of oil pressure inside a reservoir.
2. Background Information
Japanese Unexamined Patent Publication No. 9-42356A has disclosed a hydraulic shock absorber with a self leveling function for a vehicle height. This hydraulic shock absorber is equipped with a relief valve to regulate a pressure increase in a reservoir thereof, so that when a bumping force from a road surface exerts on the hydraulic shock absorber during vehicle traveling, a rapid increase of an oil pressure in the reservoir is avoided to prevent a jolt generation due to the bump force.